FILM-COATED POWDER AND PROCESS FOR PRODUCING THE SAME

摘要

A highly functional coated powder which can be prepared not by a process comprising the hydrolysis of a metal alkoxide but by a process which can be conducted without an expensive metal alkoxide and a highly flammable organic solvent and dispense with explosion-proof facilities, is facilitated in the control of temperature and humidity, and therefore permits lowering in the production cost as a whole; and a process for the preparation thereof. The coated powder is composed of substrate particles each covered with one or more films of which at least one is a film formed from a metal salt through a reaction in an aqueous solvent under the condition of constant pH. The process does not cause the precipitation of a solid in a free state (not adhering to the particle) in the liquid phase, and can give a uniform solid film on the surface of each substrate particle, while inhibiting the particles from causing aggregation.